The present invention, in some embodiments thereof, relates to characterizing bone tissue using NMR measurements, and, more particularly, but not exclusively, to detecting changes associated with Osteoporosis and/or Osteopenia.
Akune et al, “PPARγ insufficiency enhances osteogenesis through osteoblast formation in bone marrow progenitors,” Journal of Clinical Investigation 113, 846-855 (2004), investigated the role of PPARγ, a key regulator of adipocyte differentiation, in bone metabolism.
Bergman et al, “An estimation method for improved extraction of the decay curve signal from CPMG-like measurements with a unilateral scanner,” Journal of Magnetic Resonance 245, 87-93 (2014), presents a statistical signal-processing method that can improve the sensitivity of a CPMG-like sequence for measurements of transverse-relaxation with unilateral scanners, improving the extraction of the decay curve from the noisy data.
U.S. Patent Application Publication 2012/0323110 to Blake et al, relates to an MRI scan, and the resultant signal is used to give parameters that are employed to ascertain connectivity of trabeculae in the bone of the patient and volumetric trabecular density of the bone.
Sigmund et al, “In vivo imaging of DDIF contrast in the Human Knee,” presented at Magnetic Resonance of Porous Media (MRPM), 2008, published in Poster Abstracts 10:93, 2009, relates to in vivo DDIF contrast results.
Published PCT patent application WO 2006/091091 to Van Nesselrooij et al describes a method for predicting the responsiveness to vitamin D/calcium therapy in an osteoporotic subject making use of a difference profile in NMR spectra of metabolites in a body fluid.
Yoshioka et al, “Magnetic Resonance Imaging,” Chapter 3, p. 34-48, in Section 1, “General Imaging Principles,” Elsevier Health, 2003, on pages 43-44, describes an indirect measure to assess the properties of trabecular bone often termed relaxometry or quantitative magnetic resonance (QMR).
Additional background art includes Cohen et al, “Teriparatide for idiopathic osteoporosis in premenopausal women: a pilot study,” J Clin Endocrinol Metab. 2013 May; 98(5):1971-81. doi: 10.1210/jc.2013-1172. Epub 2013 Mar. 29; Yang et al, “Influences of teriparatide administration on marrow fat content in postmenopausal osteopenic women using MR spectroscopy,” Climacteric. 2016 Jan. 8: 1-7. [Epub ahead of print]; Rickard et al, “Intermittent treatment with parathyroid hormone (PTH) as well as a non-peptide small molecule agonist of the PTH1 receptor inhibits adipocyte differentiation in human bone marrow stromal cells,” Bone 2006 December; 39(6):1361-72. Epub 2006 Aug. 10; Singhal et al, “Regional fat depots and their relationship to bone density and microarchitecture in young oligo-amenorrheic athletes,” Bone 2015 August; 77:83-90. doi: 10.1016/j.bone.2015.04.005. Epub 2015 Apr. 10; Müller-Bierl et al, “Cylinders or walls? A new computational model to estimate the MR transverse relaxation rate dependence on trabecular bone architecture,” MAGMA. 2014 August; 27(4):349-61. doi: 10.1007/s10334-013-0402-7. Epub 2013 Sep.6. Erratum in: MAGMA. 2014 October; 27(5):465; Syed et al, “Effects of estrogen therapy on bone marrow adipocytes in postmenopausal osteoporotic women,” Osteoporos Int. 2008; 19(9):1323-30; and Limonard et al, “Short-Term Effect of Estrogen on Human Bone Marrow Fat,” J Bone Miner Res. 2015; 30(11):2058-66.